Image: S4010101rev
Spec A. 'end view'
SUMMARY (Jul 21, 2005) This is a meteorite! It fell on what is now Arizona about 35,000 years ago. It is about 4.5 billion years old, originating in the dawn of the formation of our solar system. It may have once been part of the iron core of a planetoid which on collision with another body, fragmented and was sent on a course toward collision with planet Earth. This huge bollide (meteoroid) (estimated to have weighed 25 million lbs, became a meteor upon entering the Earth's atmosphere and then became a meteorite on impact. Most of its mass probably vaporized in the impact event; however, up to 30 tons of fragments, the largest weighing 639 kg, were ejected from the crater and have been collected around the crater since it was 'discovered' in 1891.
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Spec. A
BACKGROUND(June 2005):
2lbs, 10oz.(1.19318 kg) in air
2 lbs. 5oz.(1.05114 kg) in H20*
(these are primitive measurements - antique spring postal scale and a piece of string)
*specimen displaces
160 ml H20 = 7oz (0.19886 kg)
(I got the displacement by capturing runoff water in a graduated cylinder)
Calculated weight diff (in oz) is 5-7 oz, so specific gravity would be 8.4 - 6.0 (ave. 7.2)
It is ferromagnetic.
My basic guide to rocks and minerals indicates Meteorites: 7.5 spec. gravity; Magnetite: 5.2 spec. gravity.
I have 2 other 'iron' specimens labelled Magnetite and they are magnetic, but clearly different in appearance (black crystalline texture).
July 7th: [I now have expert opinion: the weight of the specimen and its displaced H2O provides the following - 1193gms/160cm3 = 7.5 Specific Gravity AND 'the real test for iron meteorites is the presence of a few percent Ni in the iron alloy' - a Scanning Electron Microscope can provide that information.} Thanks. Paul!
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Spec. A 'bottom view'
IDENTIFICATION: On July 19th, U of Minnesota Prof. Paul Weiblen, who has seen several thousand 'meteor-wrongs' as Minnesota's meteorite identification expert, confirmed that the specimen is an iron meteorite. Later, Prof Calvin Alexander compared the handwriting on the specimen against a known example and declared that this specimen is another piece of the huge Canyon Diablo meteorite which made the famous Meteor Crater in Arizona. The 6's in the accession number on the specimen match exactly the numbers on one of the University's specimens which came from the company Ward's Scientific which has been providing rock, fossil, mineral and meteorite specimens to educational institutions since 1862. Ward's was unable to confirm the information, stating "...we really have no way of telling if your sample came from Wards or not...if we sold it a long time ago, we wouldn't have any record of it anymore...sorry we couldn't be of more help."
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Spec. A 'other end'
WHAT NEXT?:The specimen has been placed in safe keeping. Prof Weiblen suggests that a slice be made and provided to a researcher who can determing the precise composition. The specimen has a beautiful patina; some commercial sellers remove the patina (usually an unattractice black) and sell the result as bright polished silver. The patina was caused by oxidation during contact with the earth's atmosphere and our sample has a beautiful natural patina. You will also see the 'thumb prints' on its surface, also caused by actual melting of the meteor.
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